Research Department, Carilion Clinic and Virginia Tech Carilion School of Medicine, Roanoke, VA 24013, USA.
Cell Immunol. 2011;270(2):95-102. doi: 10.1016/j.cellimm.2011.04.011. Epub 2011 May 5.
This study describes the role of "inflammatory" oxidized (Ox) phospholipids in regulation of rahU (PA0122) expression and biofilm formation in Pseudomonas aeruginosa (383) wild type (rahU(+)) and rahU mutant (rahU(-)) strains. Functional analysis of RahU protein from P. aeruginosa in presence of Ox-phospholipids show: (a) LysoPC modulates RahU gene/and protein expression in rahU(+) cells; (b) rahU promoter activity is increased by lysoPC and inhibited by PAPC, Ox-PAPC and arachidonic acid; the latter inhibitory effect can be reversed by lysoPC, which was enzymatically derived from PAPC; (c) biofilm formation increased in rahU(-) cells as compared to rahU(+); and (d) inhibition of rahU promoter activity by PAPC and AA (but not lysoPC) showed significantly augmented biofilm formation in rahU(+) but not in rahU(-) cells. This study shows that host derived Ox-phospholipids affect P. aeruginosa-rahU gene and protein expression, which in turn modulates biofilm formation. The accompanying paper describes the role of RahU protein in eukaryotic-host cells.
本研究描述了“炎症”氧化（Ox）磷脂在调控铜绿假单胞菌（383）野生型（rahU(+)）和 rahU 突变型（rahU(-））菌株中 rahU（PA0122）表达和生物膜形成中的作用。在存在 Ox-磷脂的情况下，对铜绿假单胞菌中的 RahU 蛋白进行功能分析，结果显示：（a）溶血磷脂酰胆碱（LysoPC）调节 rahU(+)细胞中的 RahU 基因/蛋白表达；（b）lysoPC 可增加 rahU 启动子活性，而 PAPC、Ox-PAPC 和花生四烯酸则抑制其活性；后者的抑制作用可被 lysoPC 逆转，后者是由 PAPC 酶促产生的；（c）与 rahU(+)相比，rahU(-)细胞中的生物膜形成增加；（d）PAPC 和 AA（而非 lysoPC）对 rahU 启动子活性的抑制作用在 rahU(+)细胞中显著增强了生物膜形成，但在 rahU(-)细胞中则没有。本研究表明，宿主来源的 Ox-磷脂影响铜绿假单胞菌-rahU 基因和蛋白表达，进而调节生物膜形成。相关论文描述了 RahU 蛋白在真核宿主细胞中的作用。
